Mechanically activated magnetic electric switch



United States Patent Inventors Appl. No.

Filed Patented Assignee Priority William Bowler Pierrefonds:

Pierre P. Berthiaume, Montreal, Quebec, Canada Apr. 7, 1969 Dec. 29, 1970 Canadian National Railway Company Montreal, Quebec, Canada Jan. 29, 1969 Canada MECHANICALLY ACTIVATED MAGNETIC ELECTRIC SWITCH 10 Claims, 3 Drawing Figs.

U.S. Cl ZOO/61.41, 335/206 Int. Cl H01h 3/16 Field of Search 200/61.41; 335/153, 206,205, 207

References Cited UNlTED STATES PATENTS Teutsch Hess Klatte et a1.

Raskin Brooks Primary Examiner- Robert K. Schaefer Assistant Examiner-M. Ginsburg Attorney-Larson, Taylor, Hinds, Gillis, Petry, Sarro, and

Hunt, Jr.

ZOO/61.41

335/153 335/153X ZOO/61.41 335/206X ABSTRACT: A switch has a lever arm which is depressed by the passage of a wheel. Movement of the lever arm causes a shaft to rotate which in turn moves a steel shutter. A magnet is located on one side of the shutter and a relay on the other side. Movement of the steel shutter permits the magnetic force from the magnet to impinge on the relay, causing the relay to close and give the desired signal.

PATENTEU 05029 I970 3.551.619 SHEET 1 BF 3 FIG. 1

INVENTORS W. BOWLER P. BERTHIAUME :fzzziwzzw $4;

TORNE YS PATENTEIJnmzsmm 3551,6153

sum 2 [IF 3 M rw M u M ORM R m 01 Ten 0 MLT VWR NOE [BB W P gm h l l u 2 H .VN MH {1 v6 Lu Jan G W? E m m A I t cffi K mm A J J 1: 1 i m X L MECHANICALLY ACTIVATED MAGNETIC ELECTRIC SWITCH BRIEF SUMMARY OF THE INVENTION According to the invention there is provided a wheel activated switch comprising magnetically activated reed relay means, magnet means spaced-apart from said relay means and operable on the relay means, shutter means movable from a first position interposed between the magnet means and the relay means to open said relay means and to a second position removed from said first position to close the relay means, and wheel actuable means operably connected to the shutter means for moving the shutter means between said first and second positions.

In a preferred form of the switch two sets of relay means and magnet means are provided and the shutter is moved between positions interposed between the members of one or other of the sets so that in the unactivated state the switch can provide I either an open or a closed circuit, or both.

BRIEF DESCRIPTION OF THE DRAWINGS The invention willnow be described, by way of example,

with reference to a preferred embodiment illustrated in the accompanying drawings, in which;

FIG. 1 is a top plan view of a switch according to the invention with the cover removed and partly broken away.

FIG. 2 is a front view of the switch of FIG. 1 also broken away for clarity; and

FIG. 3 is a side view of the switch of FIG. 1 also broken away for clarity.

DETAILED DESCRIPTION OF EMBODIMENT Referring to the drawings, a mounting box 1 has mounted therein wheel actuable means 2, magnet means 3 and reed relay means 4.

The wheel actuable means 2 has a shaft 5 rotatably mounted in a bearing means 6 in a wall 7 of the box 1 and in a bracket 8 secured to an adjacent wall 9 of the box 1. One end of the shaft 5 extends through the wall 7 and has secured thereto one end of a wheel actuable lever 10. A vehicle wheel-striking finger 11, in this casethe wheel of a railroad vehicle, extends at right angles to the other end of the lever 10. The finger 11 is pivotally mounted in an enlarged bore a in the end of lever 10 and rubber bushings 12 are provided to urge the finger into also secured to the shaft 5 insidethe box 1 and adjacent to the bearing 6. The arm 13 extends in a plane parallel to the plane containing the lever 10. Secured to the end of arm 13 is a shutter means in the form of a rectangular steel plate 1 4. Resilient means in the form of a flat spring 15 is mounted on the bracket 8 and acts on the arm 13 to urge the arm 13, and the lever 10, in an upward direction as seen in FIG. 2. A stop member 30 welded to the end of lever 13 has ends 300 and 30b which act on plate 31 seamed to wall 9 to limit the upward and downward movement.

An angled bracket 16 is spot welded to the floor and wall 7 of the box in a corner remote from the shaft 5. Mounted in the bracket are the magnet means 3 and the reed relay means 4.

The magnet means is spaced from the wall 7 and comprises two magnets 17 and 18 located in spaced-apart vertical relationship and spaced vertically from the bracket 16 by spacing members 19 and 20 and secured to the bracket by set screw 21. The magnets 17 and 18 are horseshoe shaped and have their poles facing the relay means 4.

Close to the wall 7 of the box is a plate 22 of insulated material secured to the bracket 16. Secured to the plate 22 in spaced-apart relationship are two reed relays 23 and 24. The relays 23 and 24 are, respectively, in the same plane as, and extend across the poles of, the magnets 17 and 18. The shutter plate 14 is perpendicular to the two planes.

A terminal block 25 is secured to the base of the box 1. A common input 26 is provided to both relays, but individual return lines 27 and 28 extend to the terminal block.

In the position shown in the drawings the shutter plate 14 is interposed between the magnet 17 and the relay 23. Thus the magnetic force from the magnet is cut off from the reed in the relay 23 which will take an open state, However, as shown also, the plate 14 is removed from between the magnet 18 and the relay 24. The reed in the relay 24 is therefore exposed to the magnetic force from magnet 18 and assumes a closed" state. It will be noted that the plate 14 is so dimensioned that movement from a position in which the set 18, 24 is open to a position in which the set 17, 23 is open results in closing of the set 18,24.

The embodiment illustrated is for use with railroad vehicles. The box 1 is secured to a railroad track so that the finger I1 is adjacent the inside of the head of a rail. When a railroad vehicle passes along the track the flange of a wheel of the vehicle contacts and depresses the finger 11 which moves the shutter, by means of the lever 10, shaft 5 and arm 13, from the position shown in the FIGS. to a position in which it is interposed between magnet 18 and relay 24, thus closing relay 23 and opening relay 24. When the railroad vehicle has passed the spring 15 returns the shutter to the position in which the relay 24 is closed and the relay 23 open.

By having the finger ll resiliently and pivotally mounted to the end of lever 10 damage to the switch is avoided. Should, for example, a braked wheel attempt to pull the finger 11 along rather than depress the lever 10, the finger will pivot in the bore 10a and reduce the stress on the lever 10.

Although the invention has been particularly described with reference to two sets of magnets and relays, it will be seen that only, one set is required to carry out the invention. The provision of two sets has the advantage that the switch can be used normally open or normally closed depending upon its function.

The invention thus provides a vehicle activated switch which is robust, needs little or no attention after installation, has a long life as it has no coacting parts except the bearings and the reed relays, and are of simple construction.

We claim:

l. A mechanically operated electrical switch mechanism comprising a magnetically actuated reed relay means having contact elements movable towards and away from each other in an operating plane, a magnet means located in said operating plane and spaced from said relay means a distance sufficiently close to activate said reed relay means, a shutter of high permeability material capable of shielding said reed relay means from said magnet means, a lever arm secured to said shutter, a shaft, means supporting said shaft for turning thereof, said lever arm being connected to said shaft such that turning of said shaft about its axis oscillates the lever arm, moving the shutter solely in a plane which plane is substantially perpendicular to said operating plane, said shutter being movable in the last said plane between a first position where it shields the magnet means from the reed relay means, and a second position where the reed relay means is acted on by the magnet means, an actuating means for applying a torque to turn the said shaft in response to an external force applied to said actuating means to move said shutter to one of said first and second positions, and a resilientrestoring means continuously acting to move the shutter to the other of said first and second positions, the restoring means being overcome by the actuating means when said force turns the shaft.

2. A switch according to claim 1, wherein the said actuating means is a wheel actuable lever fixed to the shaft, extending from the shaft and arranged to turn the shaft when engaged from above by a wheel passing thereover.

3. Switch according to claim 2 wherein a wheel-contacting finger is pivotally mounted in an enlarged bore in the end of the wheel actuable lever remote from the shaft, resilient bushings being provided to urge the finger to a position perpendicular to the lever.

4. A switch according to claim 2 comprising an enclosed mounting box, said shaft journaled in the box and extending outwardly therefrom, and said reed relay means, said magnet means, said lever arm and said shutter all being located in the 7 box, and said actuating means located outside said box and arranged on that part of the shaft outside of the box to turn the same when acted on by said wheel.

5. A switch according to claim 4, wherein said lever arm is fixed to the shaft for rotation therewith within the box, and wherein said wheel actuable lever is fixed to the part of the shaft outside ofthe box for rotation therewith.

6. A switch according to claim 1, wherein the said resilientrestoring means acts directly against the said lever arm in opposition to the force applied to the lever arm by the actuating means.

7. A switch according to claim ll, wherein said shutter is a steel plate.

between the second magnet ineafn s andthe second "relay means to open said, second relay means;

10. Switch according to claim 9, "wherein said shutter'is a steel plate. 

